Shipping a final version of the Mozilla Firefox browser for the Windows 8 "Metro" environment "would be a mistake," according to a Mozilla vice president, because of the relatively minuscule number of users on the platform.

In fact, Mozilla has never seen more than 1,000 users pre-testing the beta version of Mozilla, said Johnathan Nightingale, the vice president of Firefox, in a blog post on Friday. But on any given day, millions of of people test pre-release versions of Firefox on other platforms, he added.

"Mozilla builds software to make the world better, but we have to pick our battles," Nightingale wrote. "We’re not as tiny as we were when we shipped Firefox 1.0, but we still need to focus on the projects with the most impact for our mission; the massive scale of our competitors and of the work to be done requires us to marshal our forces appropriately."

Mozilla launched its Metro effort in 2012, Nightingale said, and the team "broke through" Microsoft's controls and began developing Firefox for x86-based versions of the platform. Mozilla never developed a version of Firefox for Windows RT using ARM chips, after the company complained in 2012 that Microsoft was locking Windows users to its own browser.

It's unclear how many users opt for the Metro version of Microsoft's own Internet Explorer versus the version designed for its desktop mode; Microsoft has never broken the two numbers out. When Net Applications said Internet Explorer commanded 48.37 percent of the desktop browser market for February, for example, the company did not differentiate between the two versions. But, combined, Windows 8 and Windows 8.1 commanded just 10.68 percent or so of the entire PC market.

A Microsoft representative was not immediately available for comment.

If Mozilla did ship a Metro version of Firefox, it would be without the requisite amount of bug testing and subsequent fixes, leaving users to find and report bugs on a "finished" product. "To ship it without doing that follow up work is not an option," Nightingale wrote.

"This opens up the risk that Metro might take off tomorrow and we’d have to scramble to catch back up, but that’s a better risk for us to take than the real costs of investment in a platform our users have shown little sign of adopting," Nightingale concluded.

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